Project Summary/Abstract Understanding weight in the context of childbearing will be important for addressing the profound obesity epidemic in the US population, particularly among women and various racial/ethnic groups. This research study will advance our understanding of the factors that may explain the racial disparity in postpartum weight retention and cardiometabolic risks among childbearing women. This study has a dual purpose of advancing methods and assessment of pregnancy, weight and obesity by applying ecological momentary assessment (EMA), which is collecting data in real time, and using mobile technology such as smartphones and other devices as a means to collect data. We will simultaneously collect measures of stress, mood, diet, physical activity, and location in real time through smartphones; as well as measures of weight using Bluetooth enabled scales. Assessing women in real time and in their real environment through existing technologies may have the potential to advance health, practice, and reduce the burden on women and providers. We will also have the ability to determine optimal points of time and frequency for data collection among a pregnant and postpartum population. This study will be an ancillary study (N=350) to the Davis GDM2 Study (N=920), which is a randomized controlled trial among a diverse population of pregnant women designed to determine differences in perinatal outcomes for two screening approaches for gestational diabetes and metabolic risk profiles of mothers and their offspring. We will follow women from their last trimester of pregnancy to nine months and collect regular EMA assessments; and link the 1 year postpartum data from the GDM2 Study. The research aims are: (1) Determine the racial disparity in PPWR from delivery through 1 year postpartum and identify the psychosocial, behavioral, and contextual/environmental factors that contribute to the racial disparity; (2) Determine the racial disparity in cardiometabolic profiles (BP, LDL/HDL, hemoglobin A1C, insulin) 1 year after delivery and identify the psychosocial, behavioral, and contextual/environmental factors that contribute to the racial disparity in cardiometabolic profiles; and (3) Explore potential behavioral and psychosocial mediators of the association between context/environment and PPWR/cardiometabolic profiles. This study is intended to support a research program with a long-term goal to understand and eliminate racial/ethnic disparities in weight and obesity in the context of childbearing. The knowledge gained from this study will be critical in effectively developing multilevel interventions, programs and policies aimed at reducing obesity among women. Furthermore, assessing critical periods during pregnancy and postpartum provides insight into developing new areas of just-in-time intervention using mobile technology.